One important property of human perception is that we do not tend to process a whole scene in its entirety at once. Instead humans pay attention selectively on parts of the visual scene to acquire information where it is needed [1]}. Different attention models have been proposed and applied in object recognition and machine translation. Mnih et al. [1]} proposed an attention mechanism to represent static images, videos or as an agent that interacts with a dynamic visual environment. Also, Ba et al. [3]} presented an attention-based model to recognize multiple objects in images. The two above-mentioned models are all with the aid of REINFORCE-like algorithms.
